1. Field of the Invention
The present invention relates generally to automatic mailbox signaling devices mounted to rural or cluster mailboxes, and more specifically to signaling devices whose operative mechanism is spring driven.
2. Description of Related Art
In rural or suburban areas, the mail carrier delivers mail to mailboxes located adjacent to roads and streets which are usually a substantial distance from the houses. The standard rural-type mailbox provides a pivotal flag on its left side which may be raised to indicate to the mail carrier that there is outgoing mail to pick up. Although the mail carrier normally lowers this pivotal flag after the outgoing mail is picked up, the flag often fails to serve as an indicator that incoming mail has been delivered because there may be no outgoing mail, and thus no need to raise the flag in the first place. In this event, there is no means to indicate whether the mail carrier has already been along the route unless an automatic signal flag has also been installed.
In order to be a genuinely practicable option to a potential user, a device which performs the function of automatically indicating that mail has been delivered must meet the following three criteria. First, the device must be sufficiently sturdy--both with regard to its own construction and to the manner in which it is mounted to a mailbox--to ensure perennial, maintenance-free operation. Second, since the user will in most cases desire to mount the device to a pre-existing mailbox, the structure of the device must be such as to require a minimum of modifications to said mailbox. In particular, the need to drill additional holes in a mailbox in order to mount a signaling device will in many instances deter potential users from procuring and installing the device. Third, the device must be easy to operate by the user. In the present instance, this requirement entails that the user be able to engage the signal flag using only one hand, since at the moment of engagement the other hand will generally be occupied with holding the mail which has just been retrieved.
An examination of the related art reveals that a wide variety of mail delivery indicators has been previously proposed. In general, however, these mail delivery indicators fail to satisfy at least one of the above three criteria for viable long-term usage. A first class of devices found in the related art comprises those signaling devices which are sufficiently sturdy in construction and attachment to ensure perennial maintenance-free operation, but which are cumbersome to mount, since their sturdy character owes in large measure to the fact that their attachment to the mailbox requires the drilling of holes in the latter. In this regard, such signal flags fail to satisfy the second criterion laid out above.
Examples of this deficiency in the prior art include the following: U.S. Pat. No. 5,366,148, granted to Schreckengost, describes a side-mounted, spring-driven signal flag with associated latch mechanism, where the mounting of both the latch and the flag requires the fashioning of several holes. U.S. Pat. No. 5,123,590, granted to Teele, exhibits a very similar design to the aforementioned patent in describing a side-mounted, spring-driven signal flag with associated latch mechanism, but this design also requires a hole to be drilled in the door of the mailbox in order to secure the latch. U.S. Pat. No. 4,171,086, granted to Hudson, describes a top-mounted signal flag operated by a gravity-driven pivot mechanism, which likewise requires a sizeable hole to be drilled on top of the mailbox for mounting purposes. U.S. Pat. No. 3,596,631, granted to Sutton, describes a top-mounted, spring-driven signal flag whose top-mounting also requires holes to be pre-drilled. Similar objections apply to the devices described by Kuntz, Jr., in U.S. Pat. No. Des. 260,319, and to Taylor in U.S. Pat. No. Des. 314,852.
Other patented signal flags are simple to mount, but owe this simplicity to a sacrifice in the sturdiness either of the device itself or of the manner in which it is mounted to the mailbox. U.S. Pat. No. 4,711,391, granted to Roge, describes a spring driven signal flag mounted with adhesive to the top of the mailbox, and retained by insertion between the top of the body of the box and the box closure when in the set position. A merely adhesive connection between mail box and signal flag is insufficient, however, given the wide variety of weather extremes to which the signal flag is subjected, as well as the mechanical stresses caused by daily use. Moreover, a spring used in conjunction with a merely adhesive mount will necessarily be weak, so as to preclude the adhesive's being dislodged by the force of the engaged spring, and therefore the latter will also be subject to rapid deterioration. Similar objections apply to U.S. Pat. No. 3,482,543, granted to Guidos, which describes a side-mounted, spring-driven signal flag and associated door-mounted holding latch, both of which are adhesively mounted to the associated mailbox.
Another type of device is described in U.S. Pat. No. 4,524,905, granted to Crist, in which a small flag is mounted to a spring clipped to the top front edge of a mailbox. The spring is necessarily weak, however, due to the fact that it is set by having its top end doubled over and inserted into the box. Consequently, it is also not fit for reliable and extended employment. A very similar deficiency must be attributed to the signal flag described in U.S. Pat. No. 4,000,847, granted to Duis, where the driving spring is itself mounted to the top latch by means of a tied knot connecting the spring to the latch.
An added difficulty with the majority of the devices constituting the related art is that they fail to meet the third criterion laid out above, namely, that the signaling mechanism be simple to engage by the user, requiring as they do the use of two hands in order to be engaged in the set position. This particular deficiency attaches to the devices disclosed in U.S. Pat. No. 5,366,148 (Schreckengost), U.S. Pat. No. 4,711,391 (Roge), U.S. Pat. No. 4,524,905 (Crist), U.S. Pat. No. 4,171,086 (Hudson), U.S. Pat. No. 4,000,847 (Duis), U.S. Pat. No. 3,596,631 (Sutton), and U.S. Pat. No. Des. 314,852 (Taylor).
For these reasons, a need is present for a mailbox signaling device as described by the present invention. Moreover, none of the above inventions and patents, taken either singly or in combination, is seen to describe the present invention as claimed.